Equifax Inc. CEO said the recent security breach, which impacted up to 143 million Americans, was the “most humbling moment in our 118-year history” and promised changes to better protect customers.

“Our top priority is doing everything we can to support affected consumers,” Richard Smith said in an op-ed published Tuesday. “Our team is focused on this effort, and we are engaged around the clock in responding to millions of inquiries from consumers. Importantly, outside investigators found no evidence of unauthorized activity on our core consumer or commercial credit reporting databases.”